us globec pan-regional synthesis: an outsider's view

Download US GLOBEC Pan-Regional Synthesis: An Outsider's View

Post on 18-Jan-2016

25 views

Category:

Documents

0 download

Embed Size (px)

DESCRIPTION

US GLOBEC Pan-Regional Synthesis: An Outsider's View. Ken Denman Canadian Centre for Climate Modelling and Analysis Meteorological Service of Canada University of Victoria & Institute of Ocean Sciences-DFO, Sidney, BC Email: ken.denman@ec.gc.ca. U. Victoria. Outline of Talk. - PowerPoint PPT Presentation

TRANSCRIPT

  • US GLOBEC Pan-Regional Synthesis:An Outsider's ViewKen Denman Canadian Centre for Climate Modelling and Analysis Meteorological Service of Canada University of Victoria &Institute of Ocean Sciences-DFO, Sidney, BC Email: ken.denman@ec.gc.ca

    U. Victoria

    US-GLOBEC Boulder Nov 06

  • Outline of TalkGLOBEC Motivation and Hypotheseswhat about the 'GLOB' part? long term and large scale Where is US GLOBEC Today?mature regional studies and capabilitiesKey Questions and Approaches'local insights' versus 'universal truths'?The State of Marine Ecosystem Modellingreuniting foodweb versus biogeochemical modelsA Look into the Futureclimate change and other human impactsthinking beyond funding

    US-GLOBEC Boulder Nov 06

  • Motivation for GLOBECThere exist hemispheric, multidecadal changes

    US-GLOBEC Boulder Nov 06

  • A Closer LookLack of synchronicity in anchovy cycles

    Negative correlation with Benguela system in S. Atlantic OceanPlots like these for your study regions would be a highly desirable but unattainable outcome of the US GLOBEC program

    US-GLOBEC Boulder Nov 06

  • Working Hypothesis #1Events such as the 'physteria hysteria' off the Carolinas, or Hurricane Katrina, capture all the news. Our society tends to react immediately and intensely to these events. But how can we respond (rather than react) as a scientific community so as to help minimize the likelihood/risk of occurrence and/or severity of such events in the future?These 'crises' & our personal, institutional and funding horizons lead us to focus on shorter term, smaller scale, 'process-level' studies We want to understand the systems we are studying well enough to 'forecast' their future behavior

    US-GLOBEC Boulder Nov 06

  • Working Hypothesis #2Definition:Global change = Environmental change resulting from human activities and from climate change both natural and anthropogenic.When GLOBEC ends, it should be seen as having put our Society in a better position to address issues of Global Change

    US-GLOBEC Boulder Nov 06

  • Yet Much Environmental Change of Consequence Occurs on ENSO to Century TimescalesStatistical predictions will likely fail as the system moves beyond the ensemble of realizations on which the statistics were based.Forecasting these timescales results in the system 'losing its memory' of initial conditionsWe must assume future forcing conditionsParameters must be formulated to adapt as the ocean environment changes

    US-GLOBEC Boulder Nov 06

  • Yet Much Environmental Change of Consequence Occurs on ENSO to Century TimescalesStatistical predictions will likely fail as the system moves beyond the ensemble of realizations on which the statistics were based. Forecasting these timescales results in the system 'losing its memory' of initial conditionsWe must assume future forcing conditionsParameters must be formulated to adapt as the ocean environment changes

    US-GLOBEC Boulder Nov 06

  • Where is US GLOBEC Today? You have completed intensive field programs on Georges Bank, in the Pacific Northwest/Alaska, & in the Southern Ocean:they combine submesoscale projects with 'monitoring' on seasonal to interannual scalesyou have developed advanced sampling technology & detailed mechanistic spatially-resolved coupled physical-biological models to capture and integrate the understanding gained from the field programs.You are about to enter into your 'Synthesis' phase and need a set of criteria to focus calls for proposals and eventually the reviewing of the proposals.You want to leave a LEGACY

    US-GLOBEC Boulder Nov 06

  • Key Questions and ApproachesCan we learn from studies 'Contrasting' the different regions studied? physically-controlled vs top-down predator controlled?dominated by event-scale phenomena, versus seasonal and longer scales?systems that 'erase the past' and reset each year (or after each 'event', e.g. El Nio, 'regime shift', etc.), versus those that integrate over multiple years and have 'memory'?1. Which scientific advances made by US GLOBEC have been 'local insights' and which ones are 'universal truths'?

    US-GLOBEC Boulder Nov 06

  • Key Questions and ApproachesPortability Index PI:

    where J(Ri) is the cost function of fitting to region Ri J(Rj // Ri) is the cost of fitting to Rj after optimizing on RiAS Arabian Sea & EP Equatorial Pacific

    [Friedrichs, M. A. M, J. Dusenberry, L. Anderson, R. Armstrong, F. Chai, J. Christian, S. Doney, J. Dunne, M. Fujii, R. Hood, D. McGillicuddy, K. Moore, M. Schartau, Y. Spitz, and J. Wiggert, 2006. Assessment of skill and portability in regional marine biogeochemical models: the role of multiple plankton groups. J. Geophys. Res., submitted July 2006]2. How much of the detail built into the regional models is 'Portable'?

    US-GLOBEC Boulder Nov 06

  • Model Intercomparisons and 'Portability'Models with multiple Phytoplankton classes (rhs) perform better than 1P models when applied to different regions (bottom panels)Simple models perform almost as well as complex models in 'local optimization' (panel b)

    [Friedrichs et al, submitted]

    US-GLOBEC Boulder Nov 06

  • Model Intercomparisons and 'Portability'EqPac: Chlorophyll constraint accounts for largest cost

    Arabian Sea (not shown): Productivity constraint more important

    Complex Models - different models with similar cost may have very different internal flows - need more observations of 'internal' variables to constrain flows

    US-GLOBEC Boulder Nov 06

  • Portability IndexLower Cost Higher PortabilityOOPS! Assimilating zooplankton data Higher Cost & Lower PortabilityWHY??

    US-GLOBEC Boulder Nov 06

  • 3.Which functional representations in our models are or can be formulated so that they vary with a changing climate?(Do our approaches allow for 'emergent'? properties?) Consider the Chlorophyll: Carbon ratio for example:our models are expressed in terms of C or N yet we estimate phytoplankton biomass from Chlorophyll, and Chlorophyll captures PAR, the light used in photosynthesiswe obtain variable based on the equation for 'balanced' Chl:C of Geider et al. 1996, 1997, andobservations/analyses from OSP during SUPER (Booth et al, 1993) & our own during 1998-2000 (Pea & Varela, in prep.) tediousour 'balanced' is based on the previous 24h PAR (Jim Christian)

    US-GLOBEC Boulder Nov 06

  • C:Chl (= 1/ ) from OSP and Shelf EdgeFirst cruise?? - Winter: low, no gradient; Summer: 40 - 100[Pea & Varela, submitted]

    US-GLOBEC Boulder Nov 06

  • C:Chl Ratio for Variable PAR at OSPSmooth black line is smooth black line is average daily PAR at OSPmid-summer clear sky PAR ~ 150+ W m-2Red line is 'balanced' 1/ for PARt-1 averaged over the upper 30 m Range ~ 25 120 gC/gChlBUT Chl changes little at OSP?

    US-GLOBEC Boulder Nov 06

  • Current State of Marine Ecosystem ModelingOver the last decade, marine ecosystem model development has diverged into several lines of more or less independent activity. These include: upper food web models incorporating individual-based models (IBMs) and life history models of herbivores and harvestable marine resources; trophic models spanning many trophic levels but focusing on harvestable marine resources; biogeochemical models coupled to physical climate models.

    US-GLOBEC Boulder Nov 06

  • End-to-End Ecosystem Modeling 'E2E'International GLOBEC/ IMBER has organized an End-to-End Ecosystem Task Team (e2e), whose goal is:to guide the development of a full ecosystem approach that links all components of the food web with comprehensive climate models to explore the impacts and feedbacks between global change (in its broadest sense) and marine food webs. (North American members: Dave Karl & Ken Denman).

    US-GLOBEC Boulder Nov 06

  • US GLOBEC Synthesis could have a goal to develop an ecosystem model that would work equally well (according to some 'cost function') in all your regional study areas, embedded in the same (ROMS?) circulation model.Need better metrics of uncertaintyNeed ensemble projections:give relative probability of different outcomesevaluate risk of the different outcomesCoupling the large scales to the small scales, i.e. downscaling

    US-GLOBEC Boulder Nov 06

  • A Look into the Future Global warming is here to stayAnnual rates of emissions of CO2 are increasing, and will continue to do so for the foreseeable future (at least 30 years, due to coal generation plants) [see next 2 slides]Polluting aerosols will be tackled and reduced due their short atmospheric lifetimes and to the more immediate threat to human health which will lead to an increase in the rate of warming (due to current cooling effect of aerosols)All C4MIP coupled carbon-climate models show a positive feedback to climate, i.e. coupled models all sequester less CO2 to land and oceans than uncoupled (Friedlingstein et al., 2006, J. Climate.)

    US-GLOBEC Boulder Nov 06

  • Stabilizing Concentrations Requires Large Decrease in Emissions from Y 2000 LevelStabilizing Concentrations at 550 ppm requiresIPCC TAR, 2001Decreasing CO2 Emissions by ~75% from present levels

    US-GLOBEC Boulder Nov 06

  • What Next? Rise in Coal-Fired Plants vs. Carbon Capture and Storage CapabilitySchiermeier, Q., News feature, Nature 442, 10 Aug. 2006.IEA estimates they will release 140 GtC cf. 165 GtCanthro. left in atmosphere in 1995About 50% will remain in atmosphere (based on last 50 years)i.e. equivalent to an increase in atmospheric CO2 of 33 ppm

    US-GLOBEC Boulder Nov 06

  • What Kind of Future? Stabilizing CO2 levels at 550 ppm by 2100 ('2 x CO2') is probably not attainable throug